This invention relates to a method and apparatus for providing call admission control in a packet network such as an internet protocol (IP) network. More particularly, a terminating endpoint of a logical connection on a packet network, e.g. an IP network, is provided with the ability to make a decision on whether to accept or reject an incoming call based on a quality of service (QoS) indicator that is based on quality of service (QoS) metrics. These metrics indicate quality of service levels for specific logical connections and are accumulated over specified time periods.
While the invention is particularly directed to the art of call admission control on a packet network, and will be thus described with specific reference thereto, it will be appreciated that the invention may have usefulness in other fields and applications. For example, the invention may be used in other environments where it is advantageous to conduct connectivity tests from a terminating endpoint of a connection. Moreover, the invention may be used in environments wherein it is advantageous to conduct testing prior to setting up real-time sensitive packet streams that are delay/loss sensitive, such as streaming video.
By way of background, establishing a voice path in many types of networks is relatively straightforward. As such, testing for voice path assurance is likewise straightforward and reliable. For example, in a time division multiplexed (TDM) network, a static voice path is established using physical (e.g., semi-permanent) connections between endpoints on the network. As such, these physical connections between endpoints can be continuously monitored, during both the idle and busy intervals, to ensure the integrity and performance of the connection and thereby guarantee a certain level of quality. In addition, a provisionable per call voice path assurance (VPA) test (i.e. continuity test) is typically implemented to supplement the continuous monitoring of the physical connection. The originating endpoint of the voice path initiates this continuity test between itself and the terminating endpoint for some or all of the calls carried on the connection.
Such testing could be applied to a packet network, but it has drawbacks that would render such testing impracticable. For example, in packet networks such as IP networks, there are no physical (e.g. semi-permanent) connections between the originating and terminating endpoints. Connections between endpoints in a packet network such as an IP network are logical and dynamic. Sockets are provided at each endpoint to allow for packets to be communicated therebetween; however, no physical or semi-permanent path is maintained. Therefore, continuous monitoring to ensure connectivity is not practically possible. As a consequence, there is some probability that attempts to establish new logical connections across an IP network may fail or may result in low quality logical connections. Of course, neither outcome is desirable.
The present invention contemplates a new and improved call admission control, initiated at the terminating endpoint of a logical connection, that resolves the above-referenced difficulties and others.